Republican presidential candidate Mitt Romney speaks to suporters at a campaign rally in Palm Beach, Fla. Monday was the last day of campaining throughout the state for candidates with the Republican primary happening Tuesday.

Republican presidential candidate Sen. John McCain greets supporters as he arrives at a rally in Orlando, Fla. After winning South Carolina's Republican primary, McCain is looking for another victory in Florida in its Jan. 29 primary.

Fort Myers, Fla. — As a matter of logic, Mitt Romney would seem to have an edge going into Florida's Republican primary on Tuesday. The economy is the No. 1 issue, and the former Massachusetts governor clearly has the strongest economic portfolio of the Republican presidential candidates, as a megawealthy businessman, turnaround artist of the 2002 Olympics, and a state chief executive.

Sen. John McCain of Arizona, neck and neck with Mr. Romney in Florida polls, is less well versed in economics than he is in security matters, by his own admission. But voter decisions are never that simple. And in a state that skews toward older, more experienced voters, electability also looms large.

Polls show Mr. McCain doing better in general election matchups than Romney, and that could help McCain.

Even though independent voters are shut out of Florida's primary, making this the first "closed" contest of the 2008 nominating season, "we can't downplay the fact that some would see [McCain's] appeal to independents as a plus," she adds. "Bottom line here, people are looking with part of an eye on the primary, and 1 1/2 eyes on the general."

Whoever wins here will get a shot of momentum going into Tsunami Tuesday, the 21 primaries and caucuses around the country on Feb. 5, with 41 percent of the total GOP delegates in play. Floridians know their vote matters: Between the two major parties, nearly a million people either voted early or cast absentee ballots, a sign of the hotly contested races on both sides.

For Rudolph Giuliani, the former mayor of New York who has staked his candidacy on doing very well here, if not winning, his only hope rests on having banked lots of early votes when the polling places first opened Jan. 14 and he was still competitive in the polls, analysts say.

In the past two weeks, Mr. Giuliani's numbers have tanked. On Monday, McCain led Romney by 0.8 percent – both around 30 percent, and well inside the margin of error – in the RealClearPolitics.com average of recent polls, while Giuliani was at 16 percent.

Former Arkansas Gov. Mike Huckabee, who made a splash early this month by winning the Iowa GOP caucuses, appears to be near the end of his trail, with just 13 percent of the Florida Republican vote. About 23 percent of Florida voters self-identify as evangelical, and Mr. Huckabee is winning that group with 35 percent, but Romney is drawing a fair share, 20 percent, according to the latest Mason-Dixon poll.

Another important demographic group in Florida is the military, either retired or active, which combined represent 29 percent of the GOP vote. McCain would seem a natural fit for them, given his storied past as a Vietnam POW. But analysts warn against making assumptions.

"It's a base of support for him, but it's certainly not a unified solid base," says Brad Coker, managing director of Mason-Dixon who is based in Jacksonville, Fla. "Some of those retired military are very conservative, and they don't like McCain's stand on immigration and his opposition to some tax cuts."

Here on Florida's west coast, full of transplants from the Midwest, the even-tempered persona of Romney, originally from Michigan, plays well. "He's a problem-solver," says Lorraine Soderquist of Bonita Springs, attending a luncheon Saturday headlined by Romney's wife, Ann. "We need someone from the outside to shake things up."

But on that same day, just a few miles away, the fiery McCain was drawing an overflow crowd at a local tourist attraction. Hundreds stood outside, hoping just for a glimpse of the senator while many others gave up and left when they saw the crowd. McCain took a veiled swipe at Romney, saying, "I will lead, not manage." And he answered questions from the crowd, including from an antiwar heckler who seemed taken aback when given the microphone.

At a Romney event Sunday afternoon in a Latino suburb of Miami, the governor did not fill the venue or take questions. But judging a candidate's strength by crowd size is risky business. On the eve of the New Hampshire primary, Sen. Barack Obama's crowds dwarfed Sen. Hillary Rodham Clinton's – but she won the Democratic primary anyway.

In Florida, the well-financed Romney has been on the air with ads for months, while the resurgent McCain campaign has not had the resources for that. But given that many voters have only tuned in recently, and are deciding late, McCain may well have the edge on momentum. Over the weekend, he secured more newspaper endorsements than Romney, as well as the endorsements of the state's top two Republicans, Gov. Charlie Crist and Sen. Mel Martinez.

On the Democratic side, Florida's primary is just a beauty contest; no delegates will be awarded, owing to the national party's decision to punish the state for scheduling the primary early.

But Florida Democrats voted early in droves, and the result may give clues as to how Mr. Obama and Ms. Clinton are doing following Obama's overwhelming victory in Saturday's South Carolina primary. Clinton is a strong favorite here, where she holds a natural edge in a state with a large population of older women. If she does anything less than extremely well, that may portend trouble for her on Feb. 5.

Clinton also now faces another deficit on the endorsement front: On Monday, Sen. Edward Kennedy of Massachusetts announced his support for Obama, following the weekend endorsement of Obama by the only surviving child of President John Kennedy, Caroline.